Cholecystitis: acute or chronic inflammation of the gallbladder, most commonly associated with gallstones. Inflammation occurs within the walls of the gallbladder and creates a thickening accompanied by edema. Consequently, there is impaired circulation, ischemia, and eventual necrosis.

Cholelithiasis: formation of gallstones, cholesterol stones most common variety

Most often occurs in women after age 40, in postmenopausal women on estrogen therapy, in women taking oral contraceptives, and in the obese; Caucasians and Native Americans are also more commonly affected.